INDIRA SAGAR POLAVARAM PROJECT

The Polavaram Project is located in Andhra Pradesh on the river Godavari, near Polavaram village about 34 KM upstream of Kovvur,Rajahmundry and 42 KM upstream of ( Godavari Barrage) Sir Arthur Cotton Barrage, where the river emerges out of last range of the Eastern Ghats and enters the plains. The longitude and latitude of the Project site are 81 39′ 46” E and 170 16′ 53” N respectively.

The Polavaram Project is contemplated as Multi purpose Project envisaging Irrigation benefits to an extent of 7.20 Lakhs acres for the upland areas of East Godavari, Visakhapatnam Districts under Left Canal and West Godavari, Krishna Districts under Right Canal and generation of 960 MW Hydro Electric Power. In addition, this project under its left canal envisages 23.44 TMC of Water supply for industries in Visakhapatnam Township and Steel Plant, besides domestic water supply to villages and towns en route and diversion of 80 TM Cft. of water through the right canal to Krishna river to augment the supplies of Krishna Basin, indirect benefits such as development of Pisciculture and providing recreation and other benefits besides urbanisation etc.,

Dam

Earth cum Rock fill Dam, Spillway, Hydro Electric Power House of 960MW, Left and Right Connectivities

Canals

Left Main canal of length 181.50 KM and Right Main canal of length 174 KM.

Catchment area

Gross – 3,06,643 sqkm

Unintercepted (between Pochampad and Polavaram) – 2,15,957 sqkm

Availability of water in TMC: 301.38 TMC

Storage capacity of project in TMC (Gross): 194.60 TMC

Geological features

The dam site is located in the Eastern GhatRange The rocks at the right flank constitute Garnet Sellimanite Gneisses, firmed as Khondalites are predominant. Garnet Biotite Gneisses, Garnet ferrere Quartylites also occur. The right abutment consists of massive hard charkolites and leptynite, where as the left abutment rocks consist of fair weathered Khondalites.

The main river bed alluvium consists of coarse to medium sands for about 1000 m width for the left flank ‘g’ Angaluru hill. For about 360m on the right flank near the ‘g’ hill river bed alluvium consists of 25to30m clay which directly rests on rock underneath. Over the clay there is an 8m thick over burdens of sands.The foundation rocks in the river bed are mostly Garnet, Ferrous Gneisses except for stray cases of Pyroxene.